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Application of remote sensing in the description of fluvial system in dryland:A case study of Golmud distributive fluvial system,Qaidam Basin,NW China

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Journal of Palaeogeography 2022年第4期11卷 601-617页

作者： xiang-hui zhang Chang-Min zhang Wen-Jie Feng Rui Zhu Qing-Hai Xu School of Geosciences Yangtze UniversityWuhan430100Hubei ProvinceChina

Distributive fluvial systems(DFS)are widespread in drylands in the northwestern *** differences in fluvial morphology in drylands is beneficial for studying ancient rock records and the extraterrestrial surface *** remote sensing image,characterized by real-time and possibility of repeated observations,is a vital tool for recording and comparing fluvial systems in *** remote sensing technology is a method of investigating fluvial *** to the limited accuracy of satellite imagery,there are few reports on the detailed description of the fluvial system in drylands of NW *** analyze the pattern of fluvial morphology changes in the Golmud distributive fluvial system(DFS)in the Qaidam Basin,northwestern China,using satellite remote sensing and unmanned aerial vehicles(UAV).Firstly,we use Google Earth real-time image data,historical image data,and radar digital elevation data to extract geomorphological information;then the UAV remote sensing image data were used to interpret fluvial network information;finally,we use the gray-scale differential vector method to describe the fluvial *** zones have been identified in the Golmud DFS:the proximal,the medial,and the distal,by comparing the differences in topographic and geomorphic characteristics,fluvial morphologies,and sedimentary characteristics of the Golmud *** proximal slope is higher than the other two zones,and the geomorphic features are mainly gravel *** proximal fluvial morphologies are mainly large braided rivers,and sediments are more gravelly and less *** medial slope is relatively small,and the geomorphic features are mostly oasis *** medial fluvial morphologies are mainly meandering rivers associating with braided rivers,and sediments are more sandy and less *** distal slope is the lowest,and the geomorphic features are mostly oasis plains,lakes,and marsh *** distal fluvial morphologies are mainly meande

关键词： Qaidam basin Remote sensing UAV Distributive fluvial system Fluvial morphology Dryland fluvial systems

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Duodenal metastases of renal cell carcinoma： a case report

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Chinese Medical Journal 2010年第9期123卷 1228-1229页

作者： HE xiang-hui LU Ning zhang Rui ZHU Li-wei Department of General Surgery Tianjin Medical University General Hospital Tianjin 300052 China

Malignancy accounts for about 5% of upper gastrointestinal hemorrhage and needs to be treated by surgical intervention. Duodenal metastases are a rare and peculiar cause of upper gastrointestinal bleeding.1 Renal cell carcinoma （RCC） is a common cancer and distant metastases eventually develop in most cases. Metastatic sites for RCC are the lungs, bone, liver, adrenal glands and brain;

关键词： duodenum metastases renal cell carcinoma gastrointestinal hemorrhage

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Effect of FeCl_3 on Ignition Point of Coals

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Journal of China University of Mining and Technology 2006年第2期16卷 216-219页

作者： XU Dong-yao HUANG Min WANG Ya-bo WU hui-xiang zhang Bin School of Chemical and Environmental Engineering China University of Mining ＆ Technology Beijing 100083 China

The potential combustion-supporting agents for three kinds of coals were selected according to the Thermal Gravity Analysis (TG). The TG analysis shows that the addition of FeCl3 can reduce the ignition point of clarain and fusain from Guangxi and also the raw coal from Xinwen. The combustion-supporting effect of FeCl3 on the clarain is quite obvious, with the maximum reduction of ignition point reaching 90 ℃ and that of the burn-out point reaching 95 ℃. What is more, it can make the coal burn more completely. The relationship between the amount of FeCl3 and the ig- nition point was also investigated and the optimum amount of FeCl3 obtained. When FeCl3 is added in doses of 6%, 4%, 2%, and 1%, the reduction of ignition point is proportional to the amount of agent. If 6% of FeCl3 is added, the combus- tion-supporting effect is very significant; while if only 1% of FeCl3 is added, the combustion-supporting effect can be negligible. Therefore the optimum amount of FeCl3 is between 3% and 6% for achieving an obvious combus- tion-supporting effect. In addition, the combustion supporting mechanism of FeCl3 was also studied, which is the com- bined action of chloride and iron in the compound.

关键词： TG (Thermal Gravity Analysis) combustion-supporting agent FeCl3 ignition point coal

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Modeling of LF refining process:a review

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Journal of Iron and Steel Research International 2024年第2期31卷 289-317页

作者： Zi-cheng Xin Jiang-shan zhang Kai-xiang Peng Jun-guo zhang Chun-hui zhang Qing Liu State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China Tangshan Branch Hebei Iron and Steel Co.Ltd.Tangshan063000HebeiChina Xinjiang Bayi Iron and Steel Co. Ltd.Baosteel GroupWulumuqi830022XinjiangChina

With the increasing demand for energy conservation and emission reduction,more attentions have been paid to the intelligentization,greenization and low carbonization during the transformation and upgrading of steelmaking *** furnace(LF)refining is one of the key procedures in steelmaking process and has been widely used in steelmaking plants for its high equipment matching degree,low equipment investment and outstanding refining *** to the main tasks of LF refining process,the modeling methods of temperature prediction model,slag-making model,alloying model,argon blowing model and model of inclusions behavior were systematically reviewed,and the advantages and disadvantages of each modeling method were *** addition,the technical framework for the future has also been proposed based on existing works,including classification of raw materials,graphic representation of knowledge,introduction,upgradation and management of device/equipment,customization of steelmaking,modeling of refining process,synergy of models,intelligentization of decision-making,automation of control,and digitization of processes and operations,aiming to provide a reference for the modeling and intelligent development of LF refining process.

关键词： LF refining Temperature prediction Slag-making Alloying Argon blowing Inclusion behavior Modeling method

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Insights into in-situ imbibition behavior of fracturing fluid in propped shale fractures based on nuclear magnetic resonance:A case study from Longmaxi Formation shale,Sichuan Basin,China

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Petroleum Science 2024年第1期21卷 410-429页

作者： Jing-Jing Guo Kai-xiang Di Lie-hui zhang Yu-Long Zhao hui-Ying Tang Rui-Han zhang Ye Tian National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina

Shale gas is an important component of unconventional oil and gas *** the imbibition behavior is helpful to optimize flowback parameters and enhance gas *** imbibition studies have focused on shale matrix,and the pressure conditions discussed were mostly *** initial imbibition behavior begins from propped fractures to matrix,but there are few studies working on explaining the imbibition behavior in propped fractures or the phenomenon of many shale wells exhibit higher productivity after a“soaking”***,propped fracture samples were designed for imbibition and migration *** order to accurately study the mechanism and main influencing factors of fracturing fluid imbibition and migration in propped and unpropped shale fractures under high temperature and high pressure,a series of experiments based on nuclear magnetic resonance(NMR)were carried *** showed that NMR T_(2) spectra of all samples exhibited a bimodal *** final imbibition volume of fracturing fluid was positively related to pressure and fracture *** imbibition effect of fracturing fluid was more evident in matrix pores under high *** the migration during soaking stage,the fracturing fluid gradually migrated from large pores to small pores and gradually displaced the shale gas from the matrix,thus allowing the water blocking in propped fractures to self-unlock to some *** permeability decreased in the imbibition stage,while it recovered in the migration stage to some extent.

关键词： Forced imbibition Migration Soaking NMR T_(2)spectra Propped fracture Permeability recovery

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Effect of tungsten carbide particles on microstructure and mechanical properties of Cu alloy composite bit matrix

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Journal of Iron and Steel Research International 2024年第2期31卷 519-530页

作者： Ding-qian Dong Feng-yuan He Xin-hui Chen hui Li Kai-hua Shi hui-wen Xiong Xin xiang Li zhang College of Mechanical Engineering Sichuan University of Science and EngineeringZigong643000SichuanChina State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083HunanChina Zigong Cemented Carbide Co. Ltd.Zigong643011SichuanChina Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Science and EngineeringZigong643000SichuanChina

Copper alloy composite bit matrix was prepared by pressureless vacuum infiltration,using at least one of the three kinds of tungsten carbide particles,for example,irregular cast tungsten carbide,monocrystalline tungsten carbide and sintered reduced tungsten carbide *** effects of powder particle morphology,particle size and mass fraction of tungsten carbide on the microstructure and mechanical properties of copper alloy composite were investigated by means of scanning electron microscopy,X-ray diffraction and abrasive wear test in *** results show that tungsten carbide morphology and particle size have obvious effects on the mechanical properties of copper alloy *** tungsten carbide partially dissolved in the copper alloy binding phase,and layers of Cu_(0.3)W_(0.5)Ni_(0.1)Mn_(0.1)C phase with a thickness of around 8–15μm were formed on the edge of the cast tungsten *** 45%irregular crushed fine cast tungsten carbide and 15%monocrystalline cast tungsten carbide were used as the skeleton,satisfactory comprehensive performance of the reinforced copper alloy composite bit matrix was obtained,with the bending strength,impact toughness and hardness reaching 1048 MPa,4.95 J/cm^(2) and 43.6 HRC,*** main wear mechanism was that the tungsten carbide particles firstly protruded from the friction surface after the copper alloy matrix was worn,and then peeled off from the matrix when further wear occurred.

关键词： Polycrystalline diamond compact Pressureless vacuum infiltration Copper alloy composite bit matrix Microstructure characterization Abrasive wear behavior

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Quantum weak force sensing with squeezed magnomechanics

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 27-36页

作者： Qian zhang Jie Wang Tian-xiang Lu Ran Huang Franco Nori hui Jing Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal University College of Physics and Electronic Information Gannan Normal University Theoretical Quantum Physics Laboratory Cluster for Pioneering ResearchRIKEN Center for Quantum Computing RIKEN Department of Physics University of Michigan Academy for Quantum Science and Technology Zhengzhou University of Light Industry

Cavity magnomechanics, exhibiting remarkable experimental tunability, rich magnonic nonlinearities, and compatibility with various quantum systems, has witnessed considerable advances in recent years. However, the potential benefits of using cavity magnomechanical(CMM) systems in further improving the performance of quantum-enhanced sensing for weak forces remain largely unexplored. Here we show that, by squeezing the magnons, the performance of a quantum CMM sensor can be significantly enhanced beyond the standard quantum limit(SQL). We find that, for comparable parameters, two orders of magnitude enhancement in the force sensitivity can be achieved in comparison with the case without magnon squeezing. Moreover, we obtain the optimal parameter regimes of homodyne angle for minimizing the added quantum noise. Our findings provide a promising approach for highly tunable and compatible quantum force sensing using hybrid CMM devices, with potential applications ranging from quantum precision measurements to quantum information processing.

关键词： quantum force sensing cavity magnomechanics magnon Kerr effect

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An integrative mathematical model of microwave ion thruster for mHz-frequency thrust noise analysis

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Chinese Journal of Aeronautics 2024年第4期37卷 121-136页

作者： xiang NIU hui LIU Daren YU Plasma Propulsion Laboratory Harbin Institute of TechnologyHarbin 150001China

Many high-precision space missions need thrusters to produce thrust with low noise to compensate for disturbances and ensure satellite platform stability. Microwave ion thruster is characterized with a wide thrust range and potential for these missions. A cost-effective and accurate mathematical model is crucial for mHz-frequency thrust noise analysis and feedback controller design. The Particle-In-Cell(PIC) and global models are two common simulation tools. The PIC model is characterized with high accuracy but huge computation cost, which is difficult to analyze long-time performance characteristics. Now, the global model is only used for the discharge chamber with low accuracy and cannot reflect ion extraction properties. In this paper, an integrative mathematical model is built for a 1-cm microwave ion thruster and can reflect ion beamlet divergence and impingement on the Accelerator Grid(AG). Simulation results show good agreement with experiments at 0.06 sccm. However, the model demonstrates worse consistency with experiments when the flux increases to 0.1 sccm, which may be because the influence of neutral gas on the Electron Cyclotron Resonance(ECR) is not considered in the model. A long-time(1000 s) simulation is conducted with this model under 35 μN. It takes 3 hrs, and the thrust noise reaches 1 μN/Hz^(0.5) at 1 mHz.

关键词： Electric propulsion Microwave ion thruster Integrative model Sheath property Ion beamlet divergence Thrust noise Plasma

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Synthesis,chemical bonding and reactivity of new medium-sized polyarsenides

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Chinese Chemical Letters 2024年第7期35卷 497-501页

作者： Xu-hui Yue xiang-Wen zhang hui-Min He Lei Qiao Zhong-Ming Sun State Key Laboratory of Element-Organic Chemistry Tianjin Key Lab for Institution Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China Department of Physics Institute of Computational and Applied PhysicsTaiyuan Normal UniversityJinzhong 030619China

Gaining an understanding of the growth mechanism from single atoms to clusters and bulk materials continues to present a ***,it is important to explore the evolving trends of clusters in the structure and properties during the size *** this work,we report the synthesis and characterization of two medium-sized chain-like polyarsenic anions.[As_(21)]^(3-)represents a trimeric example of polyarsenic anion assembled through oxidative coupling of As_(7)^(3-)*** anion As_(18)^(4-)included in[As_(18)MO_(2)(CO)_(8)]^(4-)is regarded as formed by two realgar-type As_(8)subunits connected by a dinuclear AsAs *** As_(18)cluster was previously predicted by theory,and this is the first time successfully synthesized using wet chemistry ***,small-sized polyarsenides As_(2)^(2-)and As_(10)^(2-)were found in compound[K(18-crown-6)]_(3)[As_(10)]_(0.5)[As_(4){Mo(CO)_(3)}_(2)]_(0.5)·*** these,the former exhibits coordination with metal ***-crystal X-ray diffraction combined with quantum chemical calculations revealed the formation of double bonded As_(2)^(2-)stabilized by metal carbonyl *** work demonstrates a novel synthetic approach for the preparation of new polyarsenides and highlights their intriguing bonding characteristics,laying the foundation for the synthesis of such compounds and paving the way for their potential applications.

关键词： Polyarsenide Zintl anions Chain-like cluster DFT calculations AdNDP

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Regio-and Stereoselective Polymerization of Bio-based Ocimene by Rare-Earth Metal Catalysts

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Chinese Journal of Polymer Science 2024年第2期42卷 223-229,I0008页

作者： Qi-Yuan Wang Li-Peng Sang Zhen zhang Yang Jiang hui Tian Xia Zhao xiang Guo Shi-hui Li State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China Science and Technology on Aerospace Chemical Power Laboratory Hubei Institute of Aerospace ChemotechonologyXiangyang441003China Shanxi Coal Chemical Industry Technology Research Institute Xi’an710000China Hubei Institute of Aerospace Chemotechonology Xiangyang441003China

Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-sandwich benzyl fluorenyl scandium complex 4 and pyridyl-methylene-fluorenyl rare-metal complexes 5a–5c. Complexes 1, 4 and 5a–5c show trans-1,2-regioselectivities and high activities, of which 5c exhibits excellent isoselectivity(mmmm>99%). Conversely, complexes 2 and 3 promote β-ocimene polymerization to produce isotactic cis-1,4-polyocimenes(cis-1,4>99%, mm>95%). Diblock copolymers cis-1,4-PIP-block-cis-1,4-POc and cis-1,4-PBD-block-cis-1,4-POc are obtained in one-pot reactions of β-ocimene with isoprene and butadiene using complex 3. Epoxidation and hydroxylation of polyocimene afford functionalized polyolefins with enhanced T_(g)(from-20 ℃ to 79 ℃ and 74 ℃) and hydrophilicity.

关键词： Biobased monomer Terpenes Ocimene Rare-earths Polymerization Regio/stereoselectivity Elastomer

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